Methods of patterning and making masks for three-dimensional substrates

ABSTRACT

The present invention provides a method of making a mask for patterning a three-dimensional substrate. A mandrel includes a form machined in a surface corresponding to a shape of the substrate. A layer of material is deposited in a first region of the form and a metal layer is deposited in a second region of the form. A portion of the mandrel is subsequently removed. The present invention also provides a method of patterning a three-dimensional substrate with a mask.

CLAIM OF PRIORITY

The present application claims priority to U.S. Patent Application No.61/984,693, filed Apr. 25, 2014, the entire contents of which are herebyincorporated by reference.

FIELD OF THE INVENTION

The present invention generally relates to novel methods of patterningthree-dimensional substrates with masks and products formed with adeposited, patterned material thereon. The present invention alsorelates to novel methods of making masks for patterningthree-dimensional substrates.

BACKGROUND OF THE INVENTION

Consumer demand in the last decade has spurred technology to furtherminiaturize electronic devices. Specifically, the trend among consumersto reduce the size and visibility of their electronic devices may relateto their active lifestyles. That is, many consumers wish to carryelectronic devices with them at all times at least to stay engaged withthe world or to more efficiently track their personal progress. Forexample, electronic devices are currently employed in medical devices tomonitor aspects of body chemistry and administer controlled dosages ofmedications or therapeutic agents through various mechanisms.

More recently, technology companies have explored the application ofmicroelectronic devices in ophthalmic wearable lenses and contactlenses. Namely, the human eye has the ability to discern millions ofcolors, adjust easily to shifting light conditions, and transmit signalsor information to the brain at rates exceeding high-speed internetconnections. By harnessing this knowledge, properly designed lensesincorporating microelectronic devices have the ability to enhance visionand/or correct vision defects. For example, a wearable lens, preferablymade of polymers, may include a lens assembly having an electronicallyadjustable focus to augment or enhance performance of the eye. Variouscircuits and components are integrated into these polymeric structuresto achieve enhanced functionality. These components may include controlcircuits, microprocessors, communication devices, power supplies,sensors, actuators, light emitting diodes, and miniature antennas.

Electronic and/or powered contact lenses may be designed to provideenhanced vision via zoom-in and zoom-out capabilities. Alternatively,they may modify the refractive, reflective and transmission capabilitiesof the lenses. Electronic and/or powered contact lenses may also bedesigned to enhance color and resolution, display textural information,translate speech into captions in real-time, offer visual cues from anavigation system, and provide image processing and internet access, andoffer visual enhancement in low-light conditions. The properly designedelectronics and/or arrangement of electronics on lenses may furtherallow an image to be projected onto the retina without a variable focusoptic lens. Application may include novel image displays, video,multimedia and wakeup alerts.

Wearable contact lenses may include electronic sensors to detectconcentrations of particular chemicals in the precorneal (tear) film.The contact lenses may incorporate components for the noninvasivemonitoring of the wearer's biomarkers and health indicators. Sensorsbuilt into the lenses may allow diabetics to monitor blood sugar levelsby analyzing components of the tear film without having to draw blood.Separately, sensors in the lens may allow monitoring of pH, cholesterol,sodium and potassium levels as well as other biological markers. Thiscould save the patient time and money by eliminating the need to travelto a lab for blood work. In turn, sensors coupled with a wireless datatransmitter may allow a physician to have almost immediate access to apatient's blood chemistry.

With endless technological advancements, a number of difficulties existwith incorporating electronic devices on a tiny, optical-grade polymerlens. Namely, it is difficult to manufacture such components directly onthe lens due to size constraints. The components need to be integratedon about 1.5 cm² of polymer. More importantly, the electronic componentsmust be sufficiently distanced from the liquid environment of the eye toprevent contamination. It is also difficult to mount and interconnectplanar electronic devices on non-planar lens surfaces. Further, it isalso difficult to make a contact lens comfortable for the wearer giventhe existence of additional electronic components on the lens.

A need therefore exists in the art to form a three-dimensional substratewith precisely deposited layers thereon communicating withmicroelectronic devices and power sources to form electricalconnections.

Another need exists in the art to form a three-dimensional substratewith deposited layers and microelectronic devices thereon safe enough tointroduce into an ocular cavity.

A further need exists in the art to form a comfortable three-dimensionalsubstrate with deposited layers and microelectronic devices thereon forpurposes of vision correction, vision enhancement and/or monitoring awearer's biomarkers and health indicators.

SUMMARY OF THE INVENTION

In one aspect of the invention, methods of manufacturing energizedbiomedical and non-biomedical devices are provided that include steps topromote the controlled adhesion of a rigid insert, a media Insert and/orelectronic elements to a hydrogel portion.

In another aspect of the invention, a method of making a mask forpatterning a three-dimensional substrate is provided. The method mayinclude a step of providing a mandrel including a form machined in asurface thereof corresponding to a shape of the three-dimensionalsubstrate. A plating layer is deposited in a first region of the form. Ametal layer is deposited in a second region of the form, the secondregion is different from the first region. A portion of the mandrelbelow the plating layer in the first region and below the metal layer inthe second region is then removed.

In yet another aspect of the invention, a method of patterning athree-dimensional substrate with a mask is provided. The method includesa step of overlying the mask on the substrate. The mask includes a firstregion separated from a second region by a ring-shaped aperture formedalong a perimeter thereof. A layer is deposited through the ring-shapedaperture onto the substrate.

In yet another aspect of the invention, a three-dimensional substrate isprovided. The substrate includes a lens section and a non-planar sectionformed outside of the lens section. Moreover, the substrate includes aring-shaped layer formed on the non-planar section. The layer has athickness less than about 100 microns.

There has thus been outlined, rather broadly, certain aspects of theinvention in order that the detailed description may be betterunderstood, and in order that the present contribution to the art may bebetter appreciated. There are, of course, additional aspects of theinvention that will be described below and which will illustrate thesubject matter of the claims appended hereto.

In this respect, it is to be understood that the invention is notlimited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of aspects inaddition to those described and of being practiced and carried out invarious ways. In addition, it is to be understood that the phraseologyand terminology employed herein, as well as the abstract, are for thepurpose of description and should not be regarded as limiting.

DESCRIPTION OF THE DRAWINGS

In order to facilitate a fuller understanding of the invention,reference is now made to the accompanying drawings, in which likeelements are referenced with like numerals. These drawings should not beconstrued as limiting the invention and are intended only to beillustrative.

FIGS. 1A, 1B and 1C are diagrammatic representations of a firstexemplary mandrel with a single shadow mask blank in accordance with thepresent invention.

FIGS. 2A, 2B and 2C are diagrammatic representations of a secondexemplary mandrel with multiple shadow mask blanks in accordance withthe present invention.

FIGS. 3A, 3B, 3C and 3D are diagrammatic representations of an exemplarymandrel assembly with multiple shadow mask blanks in accordance with thepresent invention.

FIGS. 4A, 4B and 4C are diagrammatic representations of an exemplarytechnique for fabricating a hybrid deposition mask which incorporates anepoxy/plating mask in a machined well of a mandrel and a bridgecomponent disposed above a mandrel in accordance with the presentinvention.

FIG. 5 is a cross-sectional view of the mandrel and bridge of FIG. 4C.

FIG. 6 is a cross-sectional view of an exemplary shadow mask inaccordance with the present invention.

FIG. 7 is a diagrammatic representation of an exemplary shadow maskincluding a machined planar surface for accommodating electroniccomponents on a substrate to be masked in accordance with the presentinvention.

FIG. 8 is a diagrammatic representation of an exemplarythree-dimensional substrate with surfaces upon which interconnectionsmay be configured utilizing a mask in accordance with the presentinvention.

FIG. 9 is a diagrammatic representation of an exemplary contact lenscomprising both optics and electronics.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described with reference to the drawings, inwhich like reference numerals refer to like parts throughout.

Reference in this specification to “one embodiment” or “an aspect,” orthe like means that a particular feature, structure, or characteristicdescribed in connection with the aspect is included in at least oneaspect of the invention. The appearances of, for example, the phrases“one embodiment” or “an aspect” in various places in the specificationare not necessarily all referring to the same aspect, nor are separateor alternative aspects mutually exclusive of other aspects. Moreover,various features are described which may be exhibited by some aspectsand not by others. Similarly, various requirements are described whichmay be requirements for some aspects but not by other aspects.

Masks are generally used to deposit precise layers of a material ontospecific locations of a substrate located thereunder. Specifically,masks include blocked and unblocked regions to form a predeterminedpattern on a surface of a substrate. More specifically, these patternsare useful to form interconnections on rotationally symmetric surfacesand also on non-rotationally symmetric features such as planar surfacesof a three three-dimensional substrate. In accordance with the devicesand methods of the present invention described herein, precision masksmay be fabricated and subsequently utilized to form interconnectfeatures on complex, non-planar, three-dimensional surfaces used inophthalmic and medical applications.

In a first aspect of the invention, a method of making a mask forpatterning a non-planar substrate is provided. A mandrel is employed tofabricate the mask. A mandrel has plural definitions in the artincluding but not limited to an object utilized to shape machined work,a tool that holds or otherwise secures materials to be machined and atool that may be utilized to secure other moving tools. For purposes ofthis invention, a mandrel is a base form with one or more parts uponwhich a shadow mask is fabricated. More specifically, the mandrel is thecomponent in or on which one or more shadow masks blanks may be formed.

In an exemplary embodiment, the mandrel is substantially disc orcylindrical shaped. The mandrel includes one or more shafts located atone end that is capable of being attached to a machine lathe or similardevice. An opposite planar surface of the mandrel is machined accordingto a detailed technique wherein the surface roughness is preferably lessthan about 10 nm. This opposite planar surface of the mandrel may bemachined with one or more form wells. Preferably, the well features areless than about 100 microns. More preferably, the well features are less10 microns. The machined surface of the mandrel, including one or moreform wells, substantially matches the internal profile and features ofthe item(s) to be masked. Preferably, the masked item is athree-dimensional substrate. More preferably, the masked item is anon-planar, three-dimensional substrate. Even more preferably, themasked item is an ophthalmic lens with microelectronic devices locatedthereon.

According to one embodiment as shown in FIGS. 1A, 1B and 1C, anexemplary mandrel 100 is shown having a single form or form well 102machined into one planar face 104 thereof (See FIG. 1A). In FIG. 1B, theexemplary mandrel 100 is illustrated having a shadow mask blank plate106 that has a single shadow mask blank 108 formed thereon. FIG. 1Cillustrates one embodiment of the shadow mask blank plate 106 separatedfrom the mandrel 100. The shadow mask blank 108 may be removed from theshadow mask blank plate 106 to form the shadow mask. In this exemplaryembodiment, the mandrel 100 has a substantially cylindrical shape asonly a single form 102 is machined therein. An attachment shaft 110 forsecuring the mandrel 100 to a lathe is illustrated in phantom. In theillustrated exemplary embodiment, the form 102 comprises a number oflayers and faces that match the three-dimensional substrate upon whichthe mask is to be utilized. The mandrel 100 preferably comprisesaluminum and the single shadow mask blank 108 preferably comprisesnickel. The single shadow mask blank 108 and the shadow mask itself maybe fabricated utilizing any suitable processes, including thosedescribed herein. Preferably, the thickness of the shadow mask is lessthan about 100 microns. In addition, the ratio of thickness of theshadow mask to the width of the pattern is less than about 1. In otherwords, a 100 micron wide pattern necessitates a shadow mask that isabout 100 microns or less in thickness. Preferably, the width of theshadow mask is about 100 to 75 microns.

According to another embodiment as shown in FIGS. 2A, 2B and 2C, thereis illustrated an exemplary disc shaped mandrel 200 having multipleforms or form wells 202 machined into one planar face 204 thereof (FIG.2A), the exemplary disc shaped mandrel 200 with a shadow mask blankplate 206 including multiple shadow mask blanks 208 formed thereon (FIG.2B), and the shadow mask blank plate 206 separated from the mandrel 200(FIG. 2C). The multiple shadow mask blanks 208 may be removed from theshadow mask blank plate 206 to form the shadow masks utilizing the sameprocess as is utilized to fabricate the masks from the blanks, forexample, laser machining. In this exemplary embodiment, the mandrel 200has a substantially disc shape to accommodate the multiple forms 202machined therein. The size of the forms 202, the number of forms 202 andthe size of the mandrel 200 are all related to or dependent on oneanother. The multiple forms 202 may be arranged in any suitableconfiguration. An attachment shaft 210 for securing the mandrel 200 to alathe, illustrated in phantom, is centered behind the opposite planarface of each of the forms 202.

In the illustrated exemplary embodiment of FIG. 2A, the forms 202 eachcomprise identical patterns of layers and faces that match thethree-dimensional substrate in which the masks are to be utilized;however, different forms may be utilized on a single mandrel. Onceagain, the mandrel 200 preferably comprises aluminum and the multipleshadow mask blanks 208 preferably comprise nickel. The shadow maskblanks 208 and the shadow masks themselves may be fabricated utilizingany suitable process, including those described herein.

In accordance with an alternate exemplary embodiment as shown in FIG.3A, there is illustrated a disc shaped structure 300 with pluralopenings 302 located therethrough. This substantially disc shapedstructure 300 may be fabricated from any number of materials, includingaluminum, as described above. The through-hole openings 302 are sized toaccept single mandrel structures 304 with a single form or form well 306therein. FIG. 3B illustrates the combination of the substantially discshaped structure 300 (shown in FIG. 3A) and a plurality of the singlemandrel structures 304 form a mandrel assembly 308. The single mandrelstructure 304 and the substantially disc shaped structure 300 maycomprise any suitable means for removably attaching to one another, forexample, via threads. By having the elements interconnected in thismanner, various forms 306 may be incorporated into a single mandrelassembly 308. FIG. 3C illustrates the mandrel assembly 308 with a shadowmask blank plate 310 and associated shadow mask blanks 312. FIG. 3Dillustrates the shadow mask blank plate 310 separated from the mandrelassembly 308.

As shown in FIGS. 1-3, the one or more well forms are generallysymmetric. Specifically, a rotating tool attaches to the one or moreshafts in the mandrel coinciding with the center of the one or more wellforms. The mandrel is preferably a lightweight material to ensure lessmovement when machining a form. The mandrel also is capable ofwithstanding the stresses, strains and wear of repeated uses. In anexemplary embodiment, the mandrel is fabricated from a lightweight, highstrength to weight ratio and relatively inexpensive metallic material.Preferably, this material is aluminum because of its malleability andability to be chemically dissolved. By so doing a well form replicatingthe internal profile of the three-dimensional substrate can be obtained.

Any process known to those skilled in the art can be employed to machinethe well form. For example, a lathe or other turning machine, such as aturn-mill and a rotary transfer, may be equipped with natural orsynthetic diamond tipped tools to fabricate the one or more forms. Thisprocess is conventionally known as diamond point turning. Diamond pointturning is a multi-stage process, wherein the initial stages ofmachining are carried out utilizing a series of computer numericalcontrol lathes. Each successive lathe in the series is more accuratethan the last. In the final step of the series, a diamond tipped tool isutilized to achieve sub-nanometer level surface finishes and sub-micronform accuracies.

Alternatively, the one or more well forms may be created utilizingelectro discharge machining. Generally, electro discharge machining is amanufacturing process wherein a predetermined shape is obtainedutilizing electrical discharges to remove material, thereby creating thepredetermined shape or form. In an exemplary embodiment, the well thatis machined in the mandrel will be substantially identical to a mold ofa three-dimensional substrate to be masked. The well may include planarand non-planar surfaces. For example, a planar surface may reside in thewell to be consistent with a planar area located on the substrate toaccommodate electronic components including but not limited to dies,batteries and electrodes.

In another embodiment, and after the well form has been machined in themandrel 400 as shown in FIG. 4A, a plating mask layer 410 is depositedin the well as shown in FIG. 4B. Preferably, the plating mask comprisesa non-metallic material. In an exemplary embodiment, the non-metallicmaterial comprises epoxy. In addition, any material can be employed solong as it does not interfere with the nickel plating process.Specifically, the layer is formed in a first region of the form. Thefirst region may be formed around the perimeter of the form. Preferably,it is a 360-degree circle around the form in the shape of a ring. Thedeposited layer can preferably range from as thick as the shadow mask toa few atomic layers. Preferably, the thickness of the deposited layer isless than or equal to 100 microns. In addition, the width of thedeposited layer is preferably less than or equal to 100 microns. Duringa subsequent masking process for a three-dimensional substrate, asdiscussed in more detail below, the area where epoxy is located is usedto deposit and pattern a material on a specific location on athree-dimensional substrate. The shadow masks are reusable. For example,in one embodiment, the shadow mask may be used for a plurality ofdepositions up to several hundred. In a further embodiment, the shadowmask can be cleaned and used indefinitely.

In yet another embodiment, the shadow mask includes a bridge component420 as illustrated in FIG. 4C. Preferably, the bridge is a single,unitary structure. The bridge may be formed of any material. Preferably,the bridge is formed from the same material as the mandrel. The bridgeincludes upper and lower planar surfaces. The bridge is disposedsubstantially above the machined form located in the mandrel. It ispossible for sections of the bridge to intersect the opening in theform. In an exemplary embodiment, the bridge includes a horizontal mainbody that is perpendicular to an axial direction of the mandrel.Preferably, the height of the bridge is designed such that it does nothinder the patterning/deposition process. The bridge and mandrel aredesigned to maintain its integrity and usability of parts after thealuminum is dissolved.

A cross sectional view of the mandrel and bridge is shown in FIG. 5. Themain body 521 of the bridge includes one or more apertures. Theapertures allow more efficient coating of the parts in a subsequentstep. Preferably, the main body 521 includes a central opening 522located directly above a central portion of the mandrel. A raisedportion 505 of the mandrel located in the machined well, preferablyformed by machining, projects upward in the axial direction along acentral portion of the mandrel. Preferably, the central opening 522 ofthe bridge, e.g., female portion, is configured to mate with the raisedportion 505 of the machined well, e.g., male portion, to form a secureattachment.

The bridge also includes legs 523 located at opposite ends of the mainbody. The legs 523 extend in the axial direction of the mandrel 500 froma lower surface of the main body 521 of the bridge 520 toward an upperplanar surface of the mandrel 500 located adjacent to the machined well.Preferably, a lower surface of each of the legs 523 abuts an upperplanar surface 506 of the mandrel 500. In an exemplary embodiment, thebridge 520 comprises two legs 523 equidistantly separated from thecentral opening 522 and directly across from one another, e.g., 180degrees apart.

In a further embodiment, one or more shadow mask blanks are formed inthe form(s) of the mandrel and over the bridge via an electroplating orelectroforming process. Namely, shadow mask blanks are precursors tofinal masks which are used to pattern three-dimensional substrates. Thatis, they replicate the shape of the form which in turn replicates theshape of the three-dimensional substrate that is subsequently masked.Namely, the form is overlaid on the three-dimensional substrate having asubstantially identical match. A close overlaid design is preferred toensure optimal deposition onto the substrate. Imperfections in the formmay cause deposition of material under the mask onto undesired areas ofthe substrate. By so doing, capacitance and other electrical propertiesof electronic devices formed on the substrate may be compromised. It mayalso affect the transmission, reflection and scattering properties of anoptically clear or opaque pattern.

There are many metallic materials which may be used to fabricate theshadow mask blanks. In an exemplary embodiment, the shadow mask blank isfabricated from nickel. Preferably, the deposited metal has a thicknessless than about 100 microns. Generally, the ratio of the thickness ofthe shadow mask to the width of the pattern is less than or equal toabout 1. Thus, a 100 micron wide pattern will necessitate a shadow maskwith a thickness of 100 microns or less. Preferably, the thickness ofthe shadow mask is about 75 to 100 microns. It is noted, however, thatthe thickness of the shadow mask blank may vary depending on theapplication.

The process to form the shadow mask blank may change from electroformingto another suitable process. Electroforming is a well-known metalforming process wherein thin parts are fabricated utilizing anelectroplating process. Electroforming is employed in instances wherethe part to be fabricated has extreme tolerances or complexity.Electroplating is a process in which metal ions in a solution are movedby an electric field to coat or plate a metal skin onto a base which isthen removed after plating is complete. Because of the nature of theprocess, high fidelity structures may be produced with this technique.In other words, electroforming reproduces the form exactly without anyshrinkage or distortion.

In an exemplary embodiment, the thickness of the deposited metal layeris less than about 100 microns. The resulting mask is superposed ontothe three-dimensional substrate for patterning one or more additionallayers. Preferably, the mask is superposed in a manner such that thereis less than about 5 microns from a front optic disposed on thesubstrate. Reduced thickness of the mask relates to an improveddimensional control of the deposited layer on the substrate which, aswill be discussed below in more detail, reduces capacitance betweenelectrical components formed on the substrate.

In a further embodiment as illustrated in FIG. 6, the deposited metal isapplied over the top planar surface of the mandrel, inside the machinedwell and over the bridge. In an exemplary embodiment, the metal layer isapplied to a second region of the form. The deposited metal isselectively applied inside the machined well along surfaces, andregions, different from the first region of the form where the platinglayer is deposited. More preferably, the deposited metal in the secondregion is adjacent to the deposited plating layer in a first region. Asshown in FIG. 6, the plating layer is removed as discussed in moredetail below according to a subsequent step of the mask forming process.

The shadow mask blank formed by the upper portion of the mandrel andbridge (and epoxy/plating mask) is then removed from the remainingportion of the mandrel. The shadow mask blank may be removed in a numberof ways including, for example, chemical or physical separation. In oneembodiment, the mandrel portion below the shadow mask blank ischemically dissolved. Preferably, less than 100 microns of aluminumbelow the metal layer and plating layer remains after the dissolvingprocess. More preferably, all of the aluminum of the mandrel below themetal layer and plating is dissolved. In another embodiment, the shadowmask blanks are physically separated from the mandrel manually or viarobotic manipulators and placed in a fixture for further processing.

In a further embodiment, after the shadow mask has been removed from themandrel, the plating mask is removed from the shadow mask. In anexemplary embodiment, the plating mask is separated from the metallayer. Preferably, removal of the epoxy plating mask is performed by athermal process. For instance, the epoxy may be vaporized or degraded tofacilitate easy removal via peeling. Chemical or plasma type etching canalso be used as long as the etching process does not affect the maskmaterial. By so doing, an aperture 601 is formed in the shadow maskhaving a ring shape around the perimeter of the mask. This aperture isidentical and consistent with the area where the epoxy plating mask wasoriginally deposited. A cross-section of the mask 600 is shown in FIG.6. As illustrated, the thickness of the shadow mask is less than orequal to about 100 microns. As illustrated in FIG. 6, the bridgecomponent can be useful for securing the upper portion of the mandrelthereto in view of removing the ring-shaped plating mask.

In yet a further embodiment, the mask may be processed with desiredpatterns. The desired pattern corresponds to the particular application,for example, electrical interconnects. The pattern may be formed in anysuitable manner utilizing, for example, laser machining, laser ablation,and/or chemical etching. In an exemplary embodiment, the pattern isformed in the shadow mask blank by laser micromachining. Accordingly,once the shadow mask blanks are removed from the mandrel, they areplaced on a holding fixture that is compatible with the laser machiningsystem. The precision of currently available laser systems makes themicromachining of extremely intricate patterns possible.

In yet another embodiment, the machined well in the mandrel, asdiscussed above, may be machined to include a non-rotationally symmetricregion. As shown in FIG. 7, the mask 700 includes a planar area 710,e.g., flat region, to accommodate an electronic device such as a die,semiconductor or electrodes. The planar area assists in providing afaster connection and response between electrical components. Alignmentfeatures may also be built into the mandrel and shadow mask so that itcan be used in automated assembly and manufacturing processes.

According to a further aspect of the present invention, a method ofpatterning a layer on a three-dimensional substrate is provided. Forinstance the completed masks are transferred from the lasermicromachining fixture to a temporary securement to the substrate thatis to be masked to create a final product. For example, if the finalproduct is to be utilized as the substrate for electrical interconnectson an insert for a powered contact lens, then the shadow mask may besecured to the front optic by a specialized fixture that would allow forthe interconnect material to be deposited onto the substrate through theopenings in the shadow mask. In an exemplary embodiment, the material tobe deposited would pass through the 360-degree, ring-shaped apertureformed in the shadow mask. Any suitable deposition process known tothose skilled in the art may be utilized so long as it is compatiblewith the substrate.

In an exemplary embodiment, the three-dimensional substrate isnon-planar. More preferably, the substrate is substantially non-planar.There are numerous ways to produce a three-dimensional substrate. Insome exemplary embodiments, an injection molding technique may be usedto form the object. Other exemplary embodiments may be defined byforming various materials, like plastic films, where thermal heating ofplastic sheets and pressure from mold forming parts form the plasticsheets into three-dimensional shapes. Other exemplary embodiments mayinvolve the stamping of metallic films or electroforming of metallicmaterials into three-dimensional shapes, for example, and then coatingsuch a product with an insulating material so that discrete electricalinterconnects may be formed thereon. Other processes that may form threedimensionally shaped products like stereo lithography and voxel-basedlithography can be suitable. It may be apparent to one skilled in theart that any method that defines a three-dimensional shape which iseither made of an electrically insulative material or may be coated withan electrically insulative material can be suitable.

In an exemplary embodiment as shown in FIG. 8, a substrate 800, such asan ophthalmic lens, is provided. FIG. 8 illustrates a number ofattributes of the three-dimensional aspect of the substrate 800 bydepicting a cross-sectional cut across a portion of the substrate 800.The substrate 800 comprises an outer portion or edge 802, a centralportion or central zone 804, and intermediate features 806 and 808. Asshown, each of these intermediate features 806 and 808 has their ownlocalized three-dimensional topology.

In ophthalmic lens applications, the difference in height from the edge802 to the central zone 804 may be up to four (4) millimeters, and theintermediate features 806 and 808 may have localized height differencesthat vary between 0.001 to 0.5 millimeters with the slopes of thesidewalls thereof varying from about two (2) to about ninety (90)degrees.

A mask, is overlaid, or superposed, over the three-dimensionalsubstrate. Any shadow mask fabricated in accordance with the presentinvention can be employed to conform to the precise shape of thesubstrate 800. In other words, a shadow mask prepared in accordance withthe present invention should precisely conform to the shape of thesubstrate and be positioned as close, surface-to-surface, to thesubstrate as possible. Preferably there is less than about 15 nm oferror between the overlaid mask and a front optic located on a planararea of the substantially non-planar substrate. Specifically, when thereis space between the mask and the substrate, the depositing material maynot be limited to the sharp edges defined in the mask. Rather thematerial may spread out to features proximate to the mask's definedfeatures. In some instances, where parallel lines are placed inproximity to each other, electrical shorting between these features mayresult when the deposited features are not sharply defined.

After the mask has been aligned and placed upon its substantiallymatched, three-dimensional substrate, the shadow mask deposition processmay be performed. There are many deposition techniques which may be usedhere for thin film formation. For example, sputter deposition may beemployed. A plurality of films may also be used. For example, the filmsmay include metallic films, dielectric films, high-k dielectric films,conductive and non-conductive epoxies and other conductive andnon-conductive films. For instance, gold, transparent conductivematerials (such as ITO), dielectric (such as silicon nitride, silicondioxide, etc.) may be used. In a preferred embodiment, gold is used.Furthermore, in each of these categories, there may be a wide diversityof consistent materials that can be used in the formation of usefulfilms within the scope of this art. Without limiting this general scope,some materials of particular interest may include Indium Tin Oxide(ITO), Graphene, carbon nanoparticles and nanofibers.

After the deposition step, a film with an appropriate thickness isformed in a predetermined location on the substrate. A resulting productof a substrate with directly formed interconnections is realized.According to trials, the capacitance of the interconnect features isless than 70 picofarads. More preferably, the capacitance is less thanabout 50 picofarads. In a preferred embodiment, the capacitance is lessthan about 20 picofarads. This effect is realized by the precision ofthe ring-shaped 360-degree deposited layer on the substrate.

In yet a further embodiment, after the conductive layers, e.g., traces,have been defined, laser ablation processing may again be employed. Ifthe conductive traces or interconnect features defined by a shadow maskare not of a precision that may be obtained with laser ablation, thedefined conductive traces or interconnect features may be “trimmed” orfurther defined through the use of laser ablation. In some exemplaryembodiments, such trimming may result in improvements in throughput,since features very close to the desired finished product may be formedby shadow masking and then changed in small manners by laser ablation.

An exemplary powered or electronic contact lens comprises the necessaryelements to correct and/or enhance the vision of patients with one ormore vision defects or otherwise perform a useful ophthalmic function.In addition, the lens may be utilized simply to enhance normal vision orprovide a wide variety of functionality. The electronic contact lens maycomprise a variable focus optic lens, an assembled front optic embeddedinto a contact lens or just simply embedding electronics without a lensfor any suitable functionality. The exemplary electronic lens may beincorporated into any number of contact lenses.

According to FIG. 9, an exemplary contact lens 900 is illustrated thatcomprises both optical and electronic components such that electricaland mechanical interconnects are required. The contact lens 900comprises an optic zone 902 that may or may not be functional to providevision correction and/or enhancement, or alternately, it may simplyserve as a substrate for the embedded electronics for any suitablefunctionality. In the illustrated exemplary embodiment, the polymer orplastic forming the optic zone 902 is extended such that it forms asubstrate 904 upon which the electronics are attached. Electroniccomponents, such as semiconductor die 906 and batteries 908, connectboth mechanically and electrically to the substrate 904. Theseelectronic components may include functional blocks including a digitalcontrol system, a lens driver, a means to provide bias to the othercircuits or blocks in the die. An optical sensor may also be includedresponsive to visible, infrared and/or other form of electromagneticradiation.

Conductive traces 912 electrically interconnect the electroniccomponents, such as the semiconductor die 906 and the batteries 908, onthe substrate 904. In the exemplary embodiment illustrated, a firstconductive trace 912 a connects semiconductor die 906 to the front opticelectrode 914, and a second conductive trace 912 b connectssemiconductor die 906 to the back optic electrode 916. An adhesive layer918 may be utilized to connect the front and back optics. The conductivetraces 912 described above are preferably fabricated utilizing the maskand masking techniques described herein. As discussed above, thedeposited layer forming the conductive trace may be ring-shaped 360degrees around the perimeter of the substrate.

Although the invention is shown and described in what is believed to bethe most practical and preferred embodiments, it is apparent thatdepartures from the specific designs and methods described and shownwill suggest themselves to those skilled in the art and may be usedwithout departing from the spirit and scope of the invention. Thepresent invention is not restricted to the particular constructionsdescribed and illustrated, but should be constructed to cohere with allmodifications that may fall within the scope of the appended claims.

What is claimed is:
 1. A method of making a mask for deposition of amaterial onto a three-dimensional substrate comprising: providing amandrel including a form machined in a surface thereof corresponding toa shape of said three-dimensional substrate; depositing a plating layeronto the surface of said form in a first region of said form; depositinga metal layer onto the surface of said form in a second region of saidform, wherein said second region is different from said first region andsaid plating layer comprises a material different from said metal layer;removing a portion of said mandrel below said plating layer in saidfirst region and said metal layer in said second region; and removingsaid plating layer from said metal layer after removing said portion ofsaid mandrel.
 2. The method of claim 1, wherein said second regionsurrounds said first region.
 3. The method of claim 1, wherein saidplating layer is ring-shaped.
 4. The method of claim 1, wherein saidplating layer is deposited around a perimeter of said form.
 5. Themethod of claim 1, wherein a width of said deposited plating layer isless than about 100 microns.
 6. The method of claim 1, wherein athickness of said deposited plating layer is less than about 100microns.
 7. The method of claim 1, wherein a thickness of said depositedmetal layer is less than about 100 microns.
 8. The method of claim 1,wherein said three-dimensional substrate is substantially non-planar. 9.The method of claim 1, wherein said three-dimensional substrate isnon-rotationally symmetric.
 10. The method of claim 1, where saidthree-dimensional substrate is for an ophthalmic lens.
 11. The method ofclaim 1, further comprising: providing a bridge connected to an uppersurface of said form.
 12. The method of claim 1, wherein removing theplating layer exposes an aperture in the metal layer.